Corrosion inhibiting composition

ABSTRACT

WHEREIN R and R&#39;&#39; are inert radicals and together may form a methylene chain and n is 2, 3, 4 or 5, and compositions containing such salts and specific extenders have been found to be effective corrosion inhibitors for aqueous and oil systems.   Fatty acid addition salts of amines of the formula

United States Patent CORROSION INHIBITING COMPOSITION 8 Claims, NoDrawings U.S. Cl 252/392, 2l/2.5, 2l/2.7, 208/47, 252/148, 252/392,252/855 E, 260/239 BC, 260/25! R, 260/309.6

Int. Cl C231 11/10, C23f l l/ 14 Field of Search 252/390,

8.55 E, 148, 392; 21/2.7, 2.5; 208/47; 260/309.6, 251 R, 239 BC [56]References Cited UNITED STATES PATENTS 2,468,163 4/1949 Blair et al.252/855 E OTHER REFERENCES Condensed Chemical Dictionary, 1961,Reinhold, p. 38

Primary Examiner-Richard D. Lovering Assistant Examiner-Irwin GluckAttorney-Robert L. Niblack ABSTRACT: Fatty acid addition salts of aminesof the formula wherein R and R are inert radicals and together may forma methylene chain and n is 2, 3, 4 or 5, and compositions containingsuch salts and specific extenders have been found to be effectivecorrosion inhibitors for aqueous and oil systems.

CORROSION INIIIBITING COMPOSITION Corrosion inhibitors are becoming moreand more important in the modern technology for the preservation of themore sophisticated equipment used in today's industry. The equipment hasto be protected against the influences of corroding gases, liquids orsolids with which it comes in contact. A really desirable inhibitor thatwould find general acceptance has so far not been found. One of thedisadvantages of today s corrosion inhibitors is the limited solubilitythey have: they are usually soluble in oil or in water, but not in bothand may therefore be applied only from either an aqueous or an oilsystem.

Oil soluble corrosion inhibitors used today are generally known to benot very efficient under severe conditions; on the other hand, the knownwater-soluble corrosion inhibitors are generally inferior to oil-solubleinhibitors.

Acid addition salts of carboxylic acids and certain amines have beenused in the past as corrosion inhibitors. These salts are usually eitherwater-soluble or oil-soluble but not soluble in both systems.

It is, therefore, an object of the present invention to provide acorrosion inhibitor which is soluble in aqueous and oil systems; it isanother object of this invention to provide a corrosion inhibitor whichis effective under severe conditions of humidity and temperature; it isa further object of this invention to provide corrosion inhibitingcompositions which can be applied through aqueous or oil systems andwhich are effective under severe conditions.

These and other objects are accomplished by providing a compositioncontaining -100 percent by weight of a higher aliphatic monoorpolycarboxylic acid addition salt of an amine of the formula hereinafterreferred to as aliphatic amine salt wherein R is hydrogen or an alkylgroup of one to eight carbon atoms, R is an aliphatic group of one toeight carbon atoms, or R and R together form a methylene chain of 2-1 1carbon atoms, n is an integer from 2 to 5, and 90-9 percent by weight ofan extender selected from (a) a liquid or solid organic amine of theformula H NR", HNR",, NR":,, R"NHR NH, or morpholine, with each R"representing an alkyl group of 1-18 carbon atoms, a hydroxy alkyl of twoto three carbon atoms or cyclohexyl, and R is an alkylene chain of twoto six carbon atoms, (b) a higher aliphatic acid addition salt of anorganic amine defined as in (a), (c) a polyhydric alcohol partiallyesterified with a fatty acid, (d) a salt between the amine of formula(A) and an aromatic or hydroxy substituted aromatic carboxylic acid, orany combination of these extenders. The above aliphatic amine salts canbe used alone, but best results are obtained when the ratio between saidsalt and an extender is at least 98:2 percent by weight, preferablybetween 8:2 and 2:8, with optimum results being obtained when the ratiois between 7:3 and 3:7. However, even when containing as little as 10percent by weight of the aliphatic amine salt," the combination productprovides excellent corrosion inhibition and such compositions can beapplied through aqueous or non-aqueous systems.

The aliphatic amine salts are those produced from carboxylic acidshaving at least eight, preferably between 1 l and 44, carbon atoms; theacids may be mono-carboxylic or polycarboxylic acids and they may besaturated or unsaturated, and the carbon chain may be branched orlinear. Particular examples are the saturated mono-carboxylic acids suchas pelargonic acid, capric acid, undecylic acid, lauric acid, tridecylicacid, myristic acid, pentadecylic acid, palmitic acid, heptadecyclicacid, stearic acid, nonadecaic acid, arachidic acid and the like;unsaturated mono-carboxylic acids such as undecilenic acid, oleic acid,elaidic acid, cetoleic acid and the like; saturated polycarboxylic acidssuch as adipic acid, suberic acid, azelaic acid, sebacic acid and thelike; and poly-unsaturated carboxylic acids such as linolenic acid,parinaric acid, arachidonic acid and the like; and fatty acids derivedfrom natural fat and oil, for example, fatty acids of linseed oil, oliveoil, cacao butter, seasame oil, ricebran oil, soybean oil, rape oil,palm oil, castor oil, cotton seed oil, coconut oil, peanut oil, tallow,wool fat and sardine oil; and hydrogenated fatty acids of sardine oiland herring oil, fatty acid or sperm oil and finback oil; polymerizedunsaturated acids, e.g., dimer acid or the polymers obtained from maleicacid/oleic acid, maleic acid/castor oil, maleic acid/dimer acid,rosin-oleic acid/maleic acid, and the like. Among these, monocarboxylicacids of llcarbon atoms and tricarboxylic acid of 35-44 carbon atoms arepreferred.

Among the amines represented by the above formula (A) are theimidazolines which may be substituted by loweralkyl groups, e.g.,l,2-dimethylimidazoline and l-methyl-Z-octylimidazoline; thetetrahydropyrimidines, e.g., l-methyll ,4,5,o-tetrahydropyrimidine,l-methyl-Z-octyl-l ,4,5,6- tetrahydropyrimidine, 1,2,4-trimethyl-l,4,5,6- tetrahydropyrimidine; or bicyclic compounds e.g.,l,5-diazabicyclo(4,2,0)octene-5, l,8-diazabicyclo( 7,2,0)undecene-8,

l,4-diaza-bicycl0( 3 ,3 ,0 )octene-octent-4, l ,8-diazabicyclo( 5,4,0)undecene-7, l,8-diaza-bicyclo( 7,4,0 tridecene-8, l,8-diaza-bicyclo( 5,3,0 )decene-7, l, l 4-diazabicyclo(ll,4,0)heptadecene-l3, etc. In thepreferred compound of formula (A), n, is 3 or 4 and R and R form amethylene chain of three to five carbon atoms.

In order to prepare the salts from the above-described carboxylic acidsand the above amines, the two components are mixed and stirred for 2-3hours at 0-l00 C. The acid and amine may be used in equimolar amounts,or an excess amount of up to 50 percent of either component may beemployed. A solvent such as an alcohol (methanol, butanol, etc.) or ahydrocarbon (pentene, benzene, toluene, etc. or another inert liquid maybe used. The salt or solution may be used in the present inventionwithout removal of excess amine, acid or solvent.

As indicated above, various extenders can be used in conjunction withthe above-defined aliphatic amine salt." One of these is an aliphatic oralicyclic amine of the type defined as (a) above. Specificrepresentatives are methylamine, diethylamine, dimethylpropylamine,laurylamine, stearylamine, oleylamine, methyllaurylamine,ethylstearylamine, methyloleylamine; mono-, di-, or triethanolamines,methyldiethanolamine; alkylenediamines with two to six carbon atoms,cyclohexylamine, dicyclohexylamine, N-alkyl andN-(hydroxyalkyl)-cyclohexylamines or dicyclohexyl-amines with one tofour carbon atoms per alkyl chain.

Another of the above-mentioned extenders is a higher aliphaticcarboxylic acid addition salt of the amino compounds just mentioned. Theacids with which these addition salts are formed are the same as thosementioned above for forming the acid addition salts referred to asaliphatic amine salts."

Another component useful as an extender is a partially esterifiedpolyhydric alcohol preferably containing 2-4 hydroxy wherein the estergroup is that derived from an aliphatic mono-carboxylic acid ofpreferably e.g., 18 carbon atoms, e.g., a mono-glyceride of lauric acid,oleic acid, stearic acid, or a diglyceride of this type; an aliphaticacid ester of a divalent alcohol, e.g., the mono-ester betweendihydroxybutane and lauric acid, an aliphatic acid ester of atetravalent alcohol, e.g., sorbitan monoor di-oleate, and the like.

The last type of extender for the above aliphatic amine salt" is thesalt formed between the amine defined by the above structural formula(A) and an aromatic carboxylic acid (preferably a monocyclicmonocarboxylic acid), e.g., benzoic acid, phenylacetic acid, cinnamicacid, phthalic acid, isophthalic acid, terephthalic acid, hemimellicacid, trimellic acid, trimesinic acid or a hydroxy-substituted aromaticcarboxylic acid such as salicyclic acid, o-hydroxycumaric acid,hydroxycinnamic acid, protocatechuic acid, vanillenic acid, resorcylicacid as well as amino-substituted carboxylic acids such as aminobenzoicacids and the like.

The new composite mixtures are prepared simply by blending the aliphaticamine salt" of formula (A) with desired extender (a), (b), (c) or (d) ora mixture thereof at a temperature between 0 and 100 C. in the presenceor absence of an inert solvent. Again, when a solvent is used, itsremoval before use of the composition is optional.

The corrosion inhibitors of the present invention are used in a simpleand conventional manner, i.e., in the same fashion as the process forapplying previously known corrosion inhibitors: the new compound isadded to water or oil to form a solution or suspension which is sprayedor otherwise applied to the surface which is to be protected fromcorrosion. The amount of the composition of the present invention usedas inhibitors is between 0.01 and 10.0 percent, preferably between 0.1and percent by weight based on the weight of the water or oil medium.The corrosion inhibitors of the present invention are applicable toiron, steel, nonferrous metals and alloys where they exhibit outstandingcorrosion preventive properties.

As outlined above, the aliphatic amine salts of this invention are usedas corrosion inhibitors in combination with one, two, three or four ofthe extenders described and defined above. The combination with two ofthe above extenders is preferred, and best results are obtained by usinga combination of the aliphatic amine salt" with extenders (a) and (c) or(a) and (d) ofthe above classes.

Where the aliphatic amine salts" are mixed with one or more extenders, awide range of proportions between the components is acceptable andproduces good corrosion inhibition. For instance, if the above aliphaticamine salt is combined with dihydroxyethylcyclohexylamine and sorbitanmonooleate, the ratio between the two extenders may vary between 100:1and 1:100, preferably between 100:10 and 100 parts by weight. in anycase, the composition so formed can be used in a concentration ofbetween 0.01 and 10.0 percent by weight in water or oil to producecorrosion inhibition.

in order to illustrate the usefulness of the present compositions,reference is made to the following examples which, of course, are notmeant to limit the invention in any respect. in these examples, allproportions and percentages are based on weight.

EXAMPLE 1 Wrought iron test pieces of 6OX80X1 mm. are pretreated asfollows: they are sanded with Emery's garnet paper No. 240, washed withalcohol and ether, dried by hot air and cooled to room temperature. Thetest pieces are then immersed into a corrosion inhibiting solution ofthe composition indicated below for a period of l-2 minutes at roomtemperature, followed by air drying. The pieces are then suspended in ahumidity cabinet" where they are exposed to air containing 98 :1 percenthumidity at 49 11 C. The air is circulated through the humidity cabinetat a rate of three times the volume of the cabinet capacity per hour.

in this example, the test pieces were immersed for about 1.5 minutes inturbine oil containing 1 percent by weight of the indicated aliphaticamine salt or in water containing 2 percent by weight of the aliphaticamine salt." The following table lists the results obtained with the twosystems, indicating the percentage of the surface of the test samplewhich shows signs of corrosion after the number of hours indicated inparenthesis after each figure. The percentage is arrived at by dividingthe surface of the iron plate into 100 equal squares and counting thesquares which are affected by this severe treatment. As a comparison, anidentical sample was pretreated and treated in identical fashion exceptfor the step of immersing it into a corrosion inhibiting system. in thiscontrol test, corrosion occurrence was 100 percent after 30 minutes.

The aliphatic amine salts" listed below are those made from equimolaramounts of the amine and the aliphatic can boxylic acid.

TABLE I 1% concentration 2% in in oils; water; percent percent Testcorrosion corrosion No. Inhibitor (hrs) (hrs.)

1 Salt; of 1,8-d1aza-bicyclo(5,4,0)undec- 21 (4) (2.6)

cue-7 and lauric acid. 2 Salt oi 1,8-diaza-bicyclo(5,4,0)undec- 61 (4)88 (2. 5)

ene-7 and stearic ac 3 Salt of 1,8-diazaicyclo(5,4,0)undec- 10 (68) 11(2. 5)

ene-7 and oleic acid. 4 Salt of 1,5-diaza-bicyc1o(4,3,0)nonene- 20 (4.I5) (2.6)

5 and iaurie acid. 5 Salt of 1,5-diaza-bicyclo(4,3,0)nonene- 60 (4) 90(2.0)

5 and stearic acid. 6 Salt of 1,5-diaza-blcyclo(4,3,0)nonene- 10 (70) 13(2. l5)

6 and oleic acid. 7 Salt of 1-methyl-2-propyl-1,4,5,6-tetra- 20 (4) 90(2. 0)

hydropyrimidine and lauric acid. 8 Salt of 1-methyl-2-propl-1,4,6,6-tetra- 63 (4) 90 (2. 0)

hydropyrimidine an stearic acid. 9 Salt of1-methyi-2-propyl1,4,6,6-tetra- 10 (65) 91 (2. 0)

hydropyrimidine and oleic acid. 10 Salt ofl-methyl2'0cty1-1,4,6,6-tetra- 20 (4) (2. 0)

hydropyrimidine and lauric acid. 11 Salt ofl-methyl-2-octyl-1,4,5,6-tetra- 10 (60) 85 (2.5)

hydropyrimidine and oleic acid. 12 Salt of 1,8diaza-blcyclo(5,4,0)undec-11 (240) 87 (2. 5)

cue-7 and dimer acid. 13 Salt, of 1,6-diaza-b1cyclo(4,3,0)nonene- I 10(210) 83 (2.5)

6 and dimer acid. 14 Salt of l-methyi-Z-prop 1-1,4,5,6-tetran 10 (230)80 (2.0)

hydropyrimidine an dimer acid. 15 Salt of 1,8-djaza-blcyclo(5.4,0)undec-6 (400) 90 (2. 6)

elmle-7 and maleic acid/oleic acid 16 Salt of1,B-diaza-bicyclo(4,3,0)nonene- 7 (300) 88 (2. 5)

5 and maieie acid/oleic acid 1:1. 17 Salt ofl-methyl-2propyl-1,4,5,6-tctra- 6 (380) 81 (2. 5)

hydropyrimidine and maleic acid/ oleic acid 1:1. 18 Salt ofl-Inethyl-Z-octyl-l,4,5,6-tetra- 5 (300) 94 (2. 6)

hydropyrimidine and malelc acid/ Oleic acid 1:1. 19 Salt; of1,8-diaza-bicyc1o(5,4,0)undec- 6 (400) 91 (2. 5)

cue-7 and maleic acid/castor oil fatty acid 1: 1. 20 Salt of1,S-diaza-bicycl0(7,3,0)dodec- 6 (380) 60 (2.6)

one-8 and maleic acid/caster oil tatty acid 1:1. 21 Salt of1-methy1-2-octy1-1,4,5,6-tetra- 6 (350) 70 (2. 6)

hydropyrimidine and maleic acid/ castor oil fatty acid 1:1. 22 Salt of1,8-diaza-bicyclo(6,4,0)undec- 3 (400) 91 (2. 5)

ens-7 and maleic acid/whale oil fatty acid/rosin 2: 1:1. 23 Salt of1,fi-diaza-bicyclo(4,8,0)noncne- 5 (400) b 90 (2. 5)

5 and maleic acid/whale oil fatty acid/rosin 2:1:1n 24...... Salt of1-methy1-2-octyi-l,4,l5,6-tetra- 10 (400) b 90 (2. 6)

hydropyrimidine and maleic acld/ Whale oil fatty acid/rosin 2:121.

@ name 011 instead of turbine 011. b 3 a concentration of inhibitor. 0Mole ratio of acids.

EXAMPLE 2 in table 11 below are listed the results obtained by followingthe procedure of example 1 in identical fashion except for using acombination of an aliphatic amine salt" together with one or moreextenders listed in table 11. The results are reported as explained inexample 1. in all examples, the combinations listed are on an equalweight basis except where a different ratio is shown. Tests 25-42 referto the use of one of the above possible extenders: in tests 25-31, analiphatic or al-' icyclic amine (a) is used; in tests 32 and 34, theextenders are an aliphatic carboxylic acid salt of an alicyclic oraliphatic amine (b); in tests 35-38, a partially esterified polyhydricalcohol (c) and in tests 39-42, an aromatic carboxylic acid salt of thecompound identified by chemical structure (11) is used as extender.

in tests 43-69, two extenders are used with the aliphatic amine salts"described: tests 43-46 use (a) and (h), 47-55 use (a) and (c), 56-58 use(a) and (d), 59-62 use (b) and (0), 63-65 use (b) and (d) and 66-69 use(0) and (d). In tests 70-85, three extenders are used in each case, (a),(b) and (c) in the first four tests, (a), (b) and (d), (a), (c), and (d)and (h), (c) and (d), respectively, in the following groups of fourtests TAB LE II 1% in oil; percent corrosion Test (hrs.)

N o. Inhibitor 25 Test com and 1 and N-cyclohexylmorpho no.

26 Test compound 1 and N-ethylmorpholine.

27. Test compound 2 and cyclohexylamine.

28 Test compound 6 and N-ethyldiethanolamine.

20 Test compound 9 and N-aminoethyloctylamlne.

30 Test compound 3 and N,N-dihydroxyethylcyclohexylamine.

31..... Test compound 22 and N -ethylethanolamine.

32 Test compound 13 and stearyl amine salt of maleic acid/oleic acid1:1.

33... Test compound 22 and ethylenediamine salt of whale oil fatty acid.

34 Test com ound 13 and diethylamine salt of o elc acid.

35 Test com ound 6 and oleyl monoglyceri e.

36 Test com ound 16 and sorbitan mondo cats.

37 Test compound 3 (7 parts) and sorbitan mono-cleats (3 parts).

38- Test compound 12 (8 parts) and sorbitan mono-oleate (2 parts).

39 Test compound 15 and phthalic acid salt of 1,2dimethyl-1,4,5,6-tetrahydropyrimidine.

40 Test compound 22 and salicylate salt of 1,8-diaza-bicyclo(5,4,0)-undecene-7 (Ratio 7:3).

41 Test compound 3/salicylate salt of 1,82-diaza-bicyclo(6,4,0)undecene-7 42 Test compound 12 and salicylate salt of1,8-diaza-bicyclo(5,4,0)- undecenc-7.

43...... Test compound 15 (3 parts) Dihydroxycth loyclohoxylamina (3parts). auto of dlcyclolloxylamino (4 parts).

it Post. compound liilillayclohox ltunlnololonto of nloyluminn tutlo .4.45 'iost compound 3/dlliydl'0Xyethylcyclohexylanline/octylic acid salt2% in water; percent corrosion (hrs.)

b so 20 iethanolamlne 5:3:2.

46 Test compound 3/ethanolamine/ octylic acid salt ofdiethylethanolamine 5:223.

47 Test compound 3lN,N-dihyd:oxy- 22 ethylcyclohexylamine/sorbitanmono-cleats 2:821.

48 Test compound 3/N,N-dihydroxyethylcyclohcxylamine/sorbitanmono-cleats 8:5:2.

49 Salt of 1,5-diaza-bicyclo(4,3,0)-nonene- 5 and myristicacid/N,N-dihydroxyethylbutylamine/sorbitan monolaurate 5:522.

50. Test compound 9/triethanolamine/ sorbitan monooleate 3:7:1.

51 Test compound /N,N-dimethy1- cyclohexylamlne/sorbitan di laurate 7:3: 2.

52. Test compound 24/N,N-dimethy1- prg ylamine/sorbltan di-laurate 53Test compound 3lN,N-dihydroxyethylcyclohex lamine/ethyicne glycol mono-oeate 8:2:2.

54 Test compound 3/N,N-dihydroxyethylcycloheXylamine/l,4-butadiolmono-oleate 5:5:2.

55. Test compound 3/N,N-dihydroxyethylcyclohexylamine/sorbltanmono-oleate 8:2:2.

56 Test compound 3/salt of 1,8-diazablcyclo(5,4,0)undecane-7 and saliclic acld/N,N-dihydroxyethy cyciohexylamine 2:2:8.

b7 Test compound 9/salt of 1,5-diazabicyclo(4,3,0) nonene-5 andp-aminobenzolc acid/triethanolamine 4: 1: 16.

58 Test compound 24lsalt of I-methyl-2-octy1-1,4,5,6-tetrahydtopyrimidine and salicylicacid/N,N-dimethylpropylamine 8:2:2.

59 Test compound 3/salt oi dicyclohexylamine and oleic acid/sorbitanmono oleate 2:5:3.

60 Test compound 12/salt of ethylenediamine and oleic acid/sorbitanno-Ql e.4 =-1=.

61 Test compound 3lsalt of ethanol- 62 Test compound 3/sa1t ofdiethanol- 63 Test compound 3/salt oi dicyclo- 64 Test com ound 3/saltof oleylamine 65. Test compound 3lsa1t of ethanol- 66 Test compound3/sorbitan mono- 67 Test compound 3/sorbltan mono- 68. Test compoundalsorbitan mono- 69 Test compound 3/sorbitan di-oleate/ 70. Testcompound 3/dimethylcyclo 71- Test compound 3/N,N-dil1ydroxy- 72. Testcompound 3/N,N-dihyd.roxy- 73 Test compound BIethanolamine/salt 75 Testcompound 3/triethanolamine/ 1:1:5.2. 76...... Test compound3/N,N-dihydroxy- 77 Test compound 3/diethanolamine/ 78 Test compound3/d1methy1cyclo- 79 Test compound 22/dimsthylcycloso Test compound3/N,N-dihydroxy 81 Test compound 12/diethanolamine/ 83 Test compound3/salt 01 N -methyl- 84 Test compound 3/salt of ethylened 85 Testcompound 3/salt of ethanol- 86 Test compound 3/dim ethylcyclo- Testcompound 3/dimethylcyclohexyl- Test compound 3/salt oi dicycloamine andoctylic acid/sorbitan mono-oleate 5:3:2.

amino and octylic acid/ethyleneglycol mono-cleats 8:2:1. 1 (l hexylamineand oleic acid/salt of 1,S-diaza-bicyclo-(5,4,0)undecene-7 and salicylicacid 5:5:1.

and ole c acid/salt of 1,8-diazabicyclo(5,4,0)undocene-7 and phthalicacid 3:5:3.

amine and oleic acid/salt of 1,8-

diaza-bicyclo (5,4,0) undecene-7 and salicylic acid 5:2:3.

oleate/salt of l,8-diaza-blcyclo(5,4,0)-

undecene-7 and phthalic acid 3:5:2.

cleats/salt of 1,8diazablcyclo(5,4,0)- undecene-7 and phthalic acidoleate/Salt oi 1,8-diaza-bicyclo(5,4,0)- undecene-7 and salicylic acidsalt 5 (200) salt of l,2-dimethyl-1,4,5,6-tetrahydgopyrimidine andsalicylic acid 1 (200) hexylamine/salt of dicyclohexylamine and oleicacid/sorbitan monooleate 221:5:2.

1 (250) ethylcyclohexylamine/salt of ethylene diamine and oleic acid/sorbitan mono-oleate 1 :2: 5 :2.

5 (20) ethyicyclohexylamine/salt 01 dic clohexylamine and oleic acid/S01 itan mono-cleats 811:1:1.

d 1 (1b) of oleylamine and oleic acid/ sorbitan mono-cleats 5:2: 1:2.

R260 amine/salt of dicyclohexylamine and oleic acid salt of1,8-diaza-bicyclo- 2( 52,4601)un ecene-7 and oleic acid 5 (200) salt 01ethylenediamine and oleic acid/salt oi 1,8-diaza-bicyolo(5,4,0)-

undecene-7 and phthalic acid d l (10) nthylcyclohoxylamlne/salt ofethylonodlamino and oleic acid/salt 0! 1 8- ethylcyclohcxylamine/salt ofethyl cne-diamino and oleic acid/salt oi 1,8-diaza-bicyclo(5,4.)undecene-7 and salicylic acid 5:2:1:2.

d 1 (15) salt oi octylamine and oleic acid/ salt of1,8-diaza-bicyolo(5,4,0)undecone-7 and salicylic acid l0:2:1:8.

1 (200) hexylamine/sorbltan mono-olcate/ salt of1,8diazabicyclo(5,4,0)undecene-7 and salicylic acid 1:23:33.

4 (250) haxyiamine/sorbltan mono-oleate/ salt ofl,8-dlaza-bicyclo(5.4,0)-

tzndiegeneq and phthalic acid ethylcyclohexylamino/sorbitanmono-oloate/salt oi 1,8-diazabicyclo(5,4,0)undecene-7 and salicylic acid5:5:1z1.

sorbitan mono-oleate/salt 01 1,8- diaza-bicyclo(5,4,0)undccenc-7 andphthalic acid 4:3:2:2.

Mole ratio of acids.

3% concentration of inhibitor. s 2% concentration of inhibitor. d 1%concentration of inhibitor.

EXAMPLE 3 The compounds and compositions of the present invention can beused as additives to corrosive liquids as illustrated in the followingtests: a corrosion inhibitory composition of the type described above isdissolved to a concentration of 0.1 percent in water and, for separatetests in a 35 percent by weight of aqueous sodium chloride solution. Atest panel made from copper or steel having a total surface area of 12cm. is suspended into such a solution at room temperature for 30 days.The weight loss of the metal piece is subsequently determined and thecorrosion stability is calculated from the equation Stability weight ofcontrolweight loss during treatment/weight of control) The followingtable shows the stabilities determined in this fashion in Compositionusedt, Steel Copper es Test compound NaCl N a C1 No. Water (percent)Water (percent) 1 Same as above but ratio 522:5. 7,

We claim:

l. A composition containing l0-98 percent by weight of an acid additionsalt between an unsubstituted aliphatic monoor polycarboxylic acidhaving 8-44 carbon atoms and an amine of the formula wherein R ishydrogen or an alkyl group of one to eight carbon atoms, R is anunsubstituted aliphatic group of one to eight carbon atoms, or R and Rtogether form a methylene chain of 2-] l carbon atoms, n is an integerfrom 2 to 5, and 90-2 percent by weight of an extender selected from (a)a liquid or solid organic amine of the formula H NR", HNR" NR"3, R"NHR"'2 or morpholine wherein each R" represents an alkyl group of l-l8 carbonatoms, a hydroxy alkyl of two to three carbon atoms or cyclohexyl and Ris an alkylene chain of two to six carbon atoms, (b) a higher aliphaticacid addition salt of an organic amine of the fonnula H NR", HNR" NR"R"NHR'NH2 or morpholine, (c a polyhydric al- 5 cohol partiallyesterified with a fatty acid, (d) a salt between the amine of formula(A) and an aromatic or hydroxy-substituted aromatic carboxylic acid, orany combination of these extenders.

2. The composition of claim 1 wherein R and R in said amine togetherform a methylene chain of 2-1 I carbon atoms.

3. The composition of claim 1 wherein R and R of said amine of formula(A) together form a methylene chain of three to five carbon atoms, n is3 or 4, and said aliphatic car boxylic acid is a monocarboxylic acid ofl l-l 8 carbon atoms or a tricarboxylic acid of 35-44 carbon atoms.

4. The composition of claim 1 containing between 30 and percent byweight of a higher aliphatic acid addition salt of an amine of formula(A) and between 70 and 30 percent by weight of any of said extenders.

5. The composition of claim 1 wherein said liquid or solid extender (a)is an amine of formula N HR", HNR" or NR" wherein each R" is selectedfrom the group consisting of an alkyl chain of 1-18 carbon atoms, ahydroxyalkyl of two to three carbon atoms and cyclohexyl.

6. The composition of claim 1 wherein R and R of said amine of formula(A) together form a methylene chain of three to five carbon atoms, n is3 or 4, and said aliphatic carboxylic acid is a monocarboxylic acid of ll-l 8 carbon atoms or a tricarboxylic acid of 35-44 carbon atoms.

7. The composition of claim 1 wherein said polyhydric alcohol is asorbitan ester.

8. The composition of claim 1 wherein said aromatic carboxylic acid is amonocyclic monocarboxylic acid.

UNITED STATES PATENToFFIcE QER'HFICATE 0F CECTIUN Patent No. 3, 625, 859Dated December 7, 1971 Inventor(s) Sei Hashimoto and Kunihiko Hirose Itis certified that error appears in the above-identified patent and thatsaid Letters Patent are hereby corrected as shown below:

In Column 2, line 16, please delete, acids of ll carbon atoms andtricarboxylic acid of 35-44" and substitute therefor: "acids of 11-18carbon atoms and tricarboxylic acid of 35-44" ir Column 2, lines 26 and27, please delete "l, 4-diazabicyclo(3, 3,0)octene-octent-4, l,8-diazabicyclo (5,4,0)- undecene7, l, 8-diaza-bicyclo (7,4,0)-" andsubstitute therefor: "l,4-diaza-bicycl0(3, 3,0)octene-4, l,8-diazabicyclo(5,4,0)undecene8, l, S-diaza-bicyclo(7,4,0)-"

In Column 2, line 64, please delete "e.g., l8" and substitute therefor:"11 l8" In Column 6, Test 76, line 42, please delete "l, 8-", pleasedelete lines 43 and 44 In Claim 1, line 19, please delete "d" Signed andsealed this 18th day of December 1973.

(SEAL) Attest.

EDWARD M. FLETCHER, JR, RENE D. TEGTI IEYER Attesting Officer ActingCommissioner of Patents UNITED STATES PATENT O FFlcE v cERmFIcATE OFCORRECTION Patent No. 3, 625, 859 1971 Dated December 7,

Inventor(s) Sei Hashimoto and Kunihiko Hirose It is certified that errorappears in the above-identified patent and that said Letters Patent arehereby corrected as shown below:

In Column 2, line 16, please delete. "acids of 11 carbon atoms andtricarboxylic acid of 35-44" and substitute therefor: "acids of 11-18carbon atoms and tricarboxylic acid of 35-44" in Column 2, lines 26 and27, please delete "1,4-diazabicyc10(3, 3,0)octene-octent-4, 1,8-diaza-bicyclo (5,4, O)- undecene-7, l, 8diazabicyclo (7,4,0)" andsubstitute therefor: "1,4-diaza-bicyclo(3, 3, O)octene-4, l,8-diazabicyclo(5,4,0)undecene-8, 1, 8-diaza-bicycl0(7,4, O)-" In Column2, line 64, please delete l8" and substitute therefor: "11 18" 'inColumn 6, Test 76, line 42, please delete "1, 8-",

please delete lines 43 and 44 a In Claim 1, line 19, pleasedelete "di"Signed and sealed this 18th day of December 1973.

(SEAL) Attest:

RENE D. TEGTMEYER Acting Commissioner of Patents EDWARD M. FLETGEER, JRAttesting Officer

2. The composition of claim 1 wherein R and R'' in said amine togetherform a methylene chain of 2-11 carbon atoms.
 3. The composition of claim1 wherein R and R'' of said amine of formula (A) together form amethylene chain of three to five carbon atoms, n is 3 or 4, and saidaliphatic carboxylic acid is a monocarboxylic acid of 11-18 carbon atomsor a tricarboxylic acid of 35-44 carbon atoms.
 4. The composition ofclaim 1 containing between 30 and 70 percent by weight of a higheraliphatic acid addition salt of an amine of formula (A) and between 70and 30 percent by weight of any of said extenders.
 5. The composition ofclaim 1 wherein said liquid or solid extender (a) is an amine of formulaN2HR'''', HNR''''2 or NR''''3 wherein each R'''' is selected from thegroup consisting of an alkyl chain of 1-18 carbon atoms, a hydroxyalkylof two to three carbon atoms and cyclohexyl.
 6. The composition of claim1 wherein R and R'' of said amine of formula (A) together form amethylene chain of three to five carbon atoms, n is 3 or 4, and saidaliphatic carboxylic acid is a monocarboxylic acid of 11-18 carbon atomsor a tricarboxylic acid of 35-44 carbon atoms.
 7. The composition ofclaim 1 wherein said polyhydric alcohol is a sorbitan ester.
 8. Thecomposition of claim 1 wherein said aromatic carboxylic acid is amonocyclic monocarboxylic acid.